Removing track pad build up

[mthreecpe]

I likely wasn't aggressive enough with the bed-in on new DTC-30s, and ended up with significant vibrations a few laps into the first session on an otherwise stock e92. I tried re-bedding on the street during lunch and no improvement.

Will these go away over a few days of street driving provided I leave the track pads on?

Is reasonable to assume that I'll be able to re-bed the track pads after (hopefully) cleaning off the rotors and having street pads on until the next event?

[dparm]

It may take another bed-in attempt, but otherwise it will go away with normal street driving. Just drive like an old lady for a week.

Otherwise, try a Flex Hone tool on a cordless drill:
https://www.amazon.com/Brush-Researc...408530&sr=8-11

Ultimately I would suggest proper bedding BEFORE you get to the track and just learning to swap between street/race pads. Can you post a pic of the rotor faces? (inside and outside)

[Ximian]

Worst case scenario, have the rotors turned.

[mthreecpe]

Here are some pics. I can't tell if re-bedding will work, or only make the problem worse with the deposits getting even bigger...kind of like a flat spot, as an analogy.

So far I have ~60 highway miles and ~10 around town miles on the car with the track pads on and no signs of the deposits getting better.

[b4hand]

I doubt they will get better. I think you should get the tool dparm posted and go from there. I had this happen to me and it was the only thing that worked.

[mthreecpe]

Originally Posted by b4hand

I doubt they will get better. I think you should get the tool dparm posted and go from there. I had this happen to me and it was the only thing that worked.

How long does it take once the rotors are off...are we talking 10 minutes per rotor or is this a full day project?

Did this completely solve the problem for you?
Thanks

[DRLane]

Originally Posted by mthreecpe

How long does it take once the rotors are off...are we talking 10 minutes per rotor or is this a full day project?

Did this completely solve the problem for you?
Thanks

It takes 10 mins per rotor. Very simple

[b4hand]

Originally Posted by mthreecpe

How long does it take once the rotors are off...are we talking 10 minutes per rotor or is this a full day project?

Did this completely solve the problem for you?
Thanks

Yep, 10 min or so. Both sides. I did a proper bed in after I did this and it's been good since then.

[kyippee]

Damn. Maybe that's why I feel vibration >70mph even though I had my street and track wheels rebalanced. My BBK's rotors look quite similar in some parts

[dparm]

Originally Posted by mthreecpe

Here are some pics. I can't tell if re-bedding will work, or only make the problem worse with the deposits getting even bigger...kind of like a flat spot, as an analogy.

So far I have ~60 highway miles and ~10 around town miles on the car with the track pads on and no signs of the deposits getting better.

Try the Flex-Hone tool. Worst case is you're out $50 and an hour of your time.

[mthreecpe]

I was advised to use Scotch brite pads to keep pressure consistent. Will drive around for a few more days on the cold track pads to see if that helps (so far not promising) and then do the hand scrub.

[dparm]

Originally Posted by mthreecpe

I was advised to use Scotch brite pads to keep pressure consistent. Will drive around for a few more days on the cold track pads to see if that helps (so far not promising) and then do the hand scrub.

I have been told by Zeckhausen Racing NOT to use that, as the fibers from those will not play nice with the brake pads.

[mthreecpe]

Inconclusive results. The front rotors are actually at 28.4mm so I'll just replace them. I spent a few minutes per front rotor with the Scotch Brite pad but didn't actually remove them from the car. Back on OEM-ish street pads, the vibration under braking is much improved but still present. I can't tell if that's simply a function of the pad change or if the quick Scotch Brite session helped too.

Once I get another track day scheduled, I'm hesitant to use the same track pads again as I don't want to ruin a $500 set of rotors. I'm happy with B-quality braking, as long as it's consistent and doesn't fall away without warning. Fresh high-temp fluid will go in shortly. Fully understanding that there is no do-it-all pad, if I get a hybrid street/track pad (i.e. 2500) can I be confident I'll at least avoid the build-up issue?

[Estoril Blue]

How are you bedding pads?

[mthreecpe]

Originally Posted by Estoril Blue

How are you bedding pads?

Back to back 8/10 stops from ~60mph down to ~20mph, followed by a 10 minute drive without touching the brakes.

New front rotors (due for replacement either way) will solve all or nearly all the pad deposit issue as I doubt the rears are that impactful and I feel the judder in the steering wheel. Hopefully putting the track pads on a few days before the next event will allow the rotors to scrub clean a bit, then I'll bed-in right before the track day, and drive around with them on the car for a few days after to re-scrub rotors.

I've heard swapping street/track pads from the same manufacturer has benefits, though I'm not sure if this actually reduces the risk of bad deposits. Happy to consume pads and tires at the track, but I need more than 1 event out of rotors!

Curious to hear advice.

[StogyBear]

Originally Posted by mthreecpe

I likely wasn't aggressive enough with the bed-in on new DTC-30s, and ended up with significant vibrations a few laps into the first session on an otherwise stock e92. I tried re-bedding on the street during lunch and no improvement.

Will these go away over a few days of street driving provided I leave the track pads on?

Is reasonable to assume that I'll be able to re-bed the track pads after (hopefully) cleaning off the rotors and having street pads on until the next event?

This happened to me with my stoptechs. Street pads created a weird layer that caused brake vibrations. I put on PFC 08s and didn't get a chance to bed them in. The first few laps were scary. Steering wheel felt like it was gonna rip my hands off it vibrated so much. After a few more laps it got better.

The second session was pretty much perfect. At the pits, the rotors looked perfectly even. Drove the car home (on PFC 08s) and I notice streaks again. Sometimes I feel like light braking causes pad deposits.

[Ximian]

Originally Posted by StogyBear

This happened to me with my stoptechs. Street pads created a weird layer that caused brake vibrations. I put on PFC 08s and didn't get a chance to bed them in. The first few laps were scary. Steering wheel felt like it was gonna rip my hands off it vibrated so much. After a few more laps it got better.

The second session was pretty much perfect. At the pits, the rotors looked perfectly even. Drove the car home (on PFC 08s) and I notice streaks again. Sometimes I feel like light braking causes pad deposits.

Your experience is a bit different because the PFC 08 pads and the stock rotors don't really need bedding in and they're abrasive enough when cold that they can take off the other pad compounds.

Sometimes, the brake pads themselves need a bit of cleaning. My garage floor is a smooth concrete so I rub the pad face gently on it back and forth. It evens out the wear on each side and cleans up any buildup that could cause issues.

The other thing everyone should do before reinstalling a pad is measure the thickness of the leading and trailing edge of each brake pad. The thinner side should be on the leading edge (meets the rotor first in its direction of movement). If the thicker side is on the leading edge, that side will get much hotter, especially when the difference in thickness is around or more than 1 mm. To even out the wear on the pad, rub it against smooth concrete or something similar as mentioned earlier.

[Bengineer330]

I feel for you. It’s annoying and it’s terrible for braking confidence when your steering wheel is shaking. I fought the same problem when I first moved to aggressive track pads. I would try to bed them on the way to the track but always end up with deposits causing the steering wheel shaking. I can say that over time like dparm said it’ll eventually go away but it’s awhile unless you daily it with a good long commute. Stop/go traffic will just prolong it.

What helped me was a guy that was paddocked next to me at a track day actually rode along with me during lunch break and said I’m not stopping hard enough. Get them brakes smoking hot, I mean really stomp on them, get up to 80mph and SLAM on them repeatedly, don’t give them any time to cool off and then don’t stop until you can smell them in the cabin, I usually can see brake dust flying around taking turns. Then drive around slow and let them cool really well. You can come to a stop for stop signs no problem just try to plan a route without stop lights you don’t want to not be moving for more than a few seconds. I do mine on HWY 57 on the way up to Road America, you feel funny doing a bunch of stops on a highway but the people that know, know.

[bbnks2]

I feel like this is a separate issue from what people refer to as "bedding in." Bedding in is for burning off factory coatings and getting an interference fit between pad and rotor. Sure there is a minute amount of material transferred to the rotor surface but heavy DEPOSITS are from overheating your pads not from "incorrect" or "lack of" bedding in.

The real issue here is the incorrect pad for the application... or the lack of cooling (brake ducts) to keep the pads happy. Or over-using the brakes... Fix these things and you won't have melted brake pads stuck to your rotors...

I would think just regular cold street driving should scrape pad deposits back off the rotor. Or maybe do a few 60-0 stops and see where that gets you. Again, without melting the pads...

[admranger]

Originally Posted by bbnks2

I would think just regular cold street driving should scrape pad deposits back off the rotor.

Cold brakes. Light braking with track pads. Hawk blues were the best at this back in the Jurassic era when I tracked the most.

[OldenburgerM3]

I had terrible brake vibrations on the track every time when I swapped to track pads as well. Tried a few different things including the Zeckhausen bedding procedure etc, but I couldn't recreate the vibrations on the street at all.
During daily driving the street pad deposits on the rotor are inevitable for me and they, while invisible, can't be erased with the track pads on track. *** Therefore I now run one/two sessions with the street pads in the front to burn off their own deposits, then swap to track pads and no more vibration. *** I've given up on brake bedding unless I get new street pads.
I should add that in order to arrive at that technique I tried a few different things. What pretty much gave it away was a frustrating day at the track where I swapped and rotated brake pads multiple times back and forth but it improved and then solved the vibrations and thus my new technique.

I run a Stoptech BBK with Stoptech Street daily and Hawk DTC70 on track days. If I ever go through the Stoptech Streets that came with the kit, I will revert back to Hawk Street 5.0 because I like those better.

[Ximian]

Originally Posted by OldenburgerM3

I had terrible brake vibrations on the track every time when I swapped to track pads as well. Tried a few different things including the Zeckhausen bedding procedure etc, but I couldn't recreate the vibrations on the street at all.
During daily driving the street pad deposits on the rotor are inevitable for me and they, while invisible, can't be erased with the track pads on track. *** Therefore I now run one/two sessions with the street pads in the front to burn off their own deposits, then swap to track pads and no more vibration. *** I've given up on brake bedding unless I get new street pads.
I should add that in order to arrive at that technique I tried a few different things. What pretty much gave it away was a frustrating day at the track where I swapped and rotated brake pads multiple times back and forth but it improved and then solved the vibrations and thus my new technique.

I run a Stoptech BBK with Stoptech Street daily and Hawk DTC70 on track days. If I ever go through the Stoptech Streets that came with the kit, I will revert back to Hawk Street 5.0 because I like those better.

My ST60 kit is pretty sensitive to the pads being installed where the thicker edge of the pad is on the leading side and the thinner edge on the trailing side. This will cause the pad to heat up unevenly and can lead to deposits. Mine happened on a cold rainy day. It was bad enough that everyone diagnosed it as warped rotors.

Measure the thickness of your pads on both ends and put the thinner side on the leading edge. If the difference between the two sides of the pad are close to 1 mm or more, shave it down. My garage floor is a smooth concrete and I rub the pads against it gently until it's both ends are more even.